The effect of Benzothiazolone‐2 on the expression of Metallothionein‐3 in modulating Alzheimer's disease

INTRODUCTION: Metallothioneins (MTs) are a class of ubiquitously occurring low‐molecular‐weight cysteine‐ and metal‐rich proteins containing sulfur‐based metal clusters. MT‐3 exhibits neuro‐inhibitory activity. The possibility to enhance the expression of MT‐3 or protect it from degradation is an attractive therapeutic target, because low levels of MT‐3 were found in brains of Alzheimer's disease (AD) patients. OBJECTIVES: The primary objective of this study was to test an enhancement of MT‐3 cellular concentration after MT‐3 binding treatment, which could prevent MT‐3 degradation. METHODS: MTT assay, flow‐cytometry, fluorescence microscopy, quantitative real‐time polymerase chain reaction, and immunodetection of MT3 were used for analysis of effect of STOCK1N‐26544, STOCK1N‐26929, and STOCK1N‐72593 on immortalized human microglia‐SV40 cell line. RESULTS: All three tested compounds enhanced concentration of MT‐3 protein in cells and surprisingly also mRNA concentration. IC50 values of tested molecules exceeded about ten times the concentration that was needed for induction of MT‐3 expression. The tested compound Benzothiazolone‐2 enhanced apoptosis and necrosis, but it was not of severe effect. About 80% of cells were still viable. There was no serious ROS‐generation and no severe decrease in mitochondria numbers or stress induced endoplasmic reticulum changes after test treatments. The selected compound showed stable hydrophobic and electrostatic interaction during MT‐3 ligand interaction. CONCLUSION: Benzothiazolone‐2 compounds significantly enhanced MT‐3 protein and mRNA levels. The compounds can be looked upon as one of the probable lead compounds for future drug designing experiments in the treatment of Alzheimer's disease.